Yes, neck pain is a tough one, whether muscle, nerve, etc. A blood clot is not very likely. I see my doctor every 3 months and he always listens to my artery there and never comments that anything is wrong but I have bad neck pain, often and at odd times.

I still remember when I was in my 20s and had to finally go to the doctor for it and the physician's assistant said I had "straightening of the spine" LOL (a made up diagnosis if one has ever heard one) and that was pulling "up" on the muscles making them hurt. He was not very helpful so I starting thinking about my life and realized I was being stubborn about some things. That night, the pain went away! Ah, stress, does it to me every time. When I would start a new job I'd get a stiff neck the first week or two at every job! Hard to work a new job with a stiff neck.

Now I have arthritis in my shoulders and know my sleeping position is not right, I sit here on a soft sofa with bad posture all day, etc. There's just so much that can go wrong.